Insole for shoes

ABSTRACT

An insole is proposed for a shoe. The insole has a flat back side in direction of the shoe outsole and a dome-shaped structure on the front side. The dome-shaped structure has a base surface of a maximum of 25% of the insole surface; the dome-shaped structure is positioned under the cuboid bone of the shoe wearer. A longitudinal axis can be associated with the dome-shaped structure at its apex, wherein the longitudinal axis of the dome-shaped structure encloses an angle (φ) in a range from 5° to 75° with the longitudinal axis of the insole.

CROSS REFERENCE TO RELATED APPLICATION

This is a U.S. national stage of application No. PCT/EP2010/062410,filed on Aug. 25, 2010. Priority is claimed on Europe, Application No.09168688.1 filed Aug. 26, 2009 the contents of which are incorporatedhere by reference.

BACKGROUND OF THE INVENTION

The invention is directed to an insole for shoes, which has a flat backside in direction of the shoe outsole with which the proposed insole isbrought into contact and a dome-shaped structure on the front side.

To allow a comprehensive appraisal of the present invention, the closedmovement cycle of a walking human will first be considered analytically.This closed movement cycle involves not only the foot but also theentire lower extremity. For this purpose, the foot must contact theground. When the foot contacts the ground, each movement of parts ofthis foot affects all of the other parts of the corresponding leg.

The walking movement of each leg is divided into the stance phase andthe swing phase. The stance phase is further differentiated into threecomponent phases; see FIG. 1 which illustrates the human gait using theexample of the right leg.

-   -   The contact phase, the first component phase of the stance        phase, begins by the foot striking the ground with the outer        edge of the heel. The tibia rotates internally and the inner        side of the foot is raised slightly. In this phase, the foot        rolls further inward until the metatarsus supports the full        weight. The tibia rotates externally and the ankle pronates        (rolls inward) by up to 8° so that the foot prepares for the        propulsive phase. In short, the foot has absorbed the shock of        contact with the ground, adapted to the uneven surface, and        flattened out. The contact phase is concluded when the forefoot        is in full contact with the ground. The primary function of this        phase is to absorb the shock when striking the ground and adapt        to different ground surfaces (adaptation).    -   The second component phase of the stance phase, the midstance        phase, begins with the forefoot fully contacting the ground and        ends with the heel lifting off from the ground. Body weight        travels over the foot when the tibia and the rest of the body        move forward. The primary function of the foot in this phase is        to store, with as little loss as possible, the energy gained        during the first component phase and reserve it for the        propulsive phase, comparable to a bouncing rubber ball.    -   The third component phase of the stance phase, the propulsive        phase, begins with the lifting of the heel; the muscles,        ligaments and tendons are flexed. The forefoot and hindfoot        together form a springboard by which the toes lift the weight of        the body (forward) off the ground. The body is propelled forward        during this component phase, and the weight is shifted to the        other foot when this other foot makes contact with the ground.        This phase has a duration of approximately 2 seconds and takes        up 33% of the entire stance phase.    -   At the start of this third component phase of the stance phase,        the subtalar joint supinates (rolls outward) and ensures that        the center of pressure remains under the outer side of the        forefoot, which ensures that the cuboid bone locks with the        navicular bone. The foot transforms from mobile adaptor to rigid        lever in order to propel the body forward during this phase. The        cuboid is exceptional in that it is the only bone in the foot        that articulates with both the metatarsal joint (tarsometatarsal        articulation or Lisfranc joint) and the tarsal joint (midtarsal        or Chopart's joint); further, it is the only bone that links the        lateral column with the transverse foot arch. Consequently, the        cuboid is the keystone of the rigid, static lateral column and        thus imparts its own stability to the foot.    -   Locking of the cuboid with respect to the navicular provides for        a very strong support through the participating ligaments and,        in so doing, spares the muscles which would otherwise be        severely tasked, since the vertical forces at this moment can        exceed 125% of the body weight. Towards the end of the        propulsive phase, unlocking of the cuboid is required after the        locking has taken place at the start of the propulsive phase. A        co-contraction of the fibularis longis (also known as peroneus        muscle) and tibialis anterior takes place, which leads to        counter-contractions and brings about a transverse pulling and        supporting effect which substantially aligns the bones of the        midtarsal region. The supporting effect of the tendons of the        peroneus longus muscle around the cuboid is essential for        control of the function of the transverse arch for stability and        adaptability. To reach the end of the propulsive phase in which        the big toe leaves the ground, the foot must now rotate        internally, otherwise known as pronation. If the cuboid were not        released or were unlocked, each joint would lose a small portion        of its movement and, therefore, also a small portion of its        forces needed for toe-off: this would lead to inhibition of        muscular force, endurance, balance and proprioception. Moreover,        there would be a tendency for lateral sprains because this        structure is basically a raising structure (supination) and the        person could not achieve a functional lowering (pronation). In        such a case, the natural flow of force through the foot        illustrated in FIG. 2 would be interrupted or limited. Before        the big toe leaves the ground, there occurs a dorsiflexion of        the big toe together with the four small toes of the same foot        and a plantarflexion of the first metatarsal bone together with        the other metatarsal bones of the same foot. The dorsiflexion of        the big toe is known as the windlass effect and is made possible        because of the contraction of the extensor hallicus longus        muscle. With the dorsiflexion of the big toe, the sesamoid bones        move forward and upward around the head of the metatarsus and        thus maximize the tension of the flexor hallicus longus muscle.

FIG. 1 shows the right-foot gait and the stance phase subdivided intoits three subphases: the contact phase, midstance phase and propulsivephase.

FIG. 2 illustrates the natural flow of force through the foot in moredetail. The flow of force begins slightly to the side in the heel andthen flows forward between the first and second metatarsal bones andexits the foot through the big toe.

Numerous authors who have addressed problems relating to heath,particularly problems of the lower extremities in humans, are convincedthrough their own observations that precisely those disabilities whichare frequently encountered in humans who wear shoes consistently and forlong periods are absent in the feet of primitive peoples who do not wearshoes: hallux valgus, plantar fasciitis, bunions, hammertoe, andgenerally painful feet are typical examples of such disabilities.

In short, it may be stated that in societies in which shoes are notworn, the foot muscles have freedom of movement and the joints remainflexible. Therefore, functional disorders are found in these humans onlyextremely rarely.

In shoe-wearing humans, shoes commonly limit the natural movements ofthe foot and the sequences for adaptive muscle activation required forstabilization of the foot structure before and during full weightbearing and during toe-off.

Various rehabilitative insoles have been proposed for alleviating thehealth problems described above. For example, U.S. Pat. No. 5,404,659suggests an insole for a shoe in which a very extensive dome-shapedstructure is provided for stimulating the golgi tendon organ. Thisdome-shaped structure makes up almost 50% of the entire surface area ofthe insole and accordingly forces the foot into a concave compulsoryposture enclosing the arch. A disadvantage in this known insole is theinhibition of the windlass effect described and, therefore, of the finaland very important part of the stance phase: the propulsive phase. Withits dome-shaped structure, the known insole aims at a region defined asthe apex of the arch of the foot by the lateral cuneiform, cuboid andnavicular bones. However, in the inventor's opinion, the dynamiclocking/unlocking of the cuboid bone, which is inhibited by the knowninsole, is fundamentally important for a natural gait with shoes. Sincethe peroneus longus embraces the cuboid, it is important that the cuboidyields. Otherwise, the peroneus is weakened. This highlights theinventor's insight that it is important to assist the foot in optimallyperforming the function intended for it by nature rather thanartificially build up the foot posture enclosing the arch by anexcessively large dome-shaped structure. Further, it has been shown thatit is rather uncomfortable to wear a shoe having the known insole.

European patent applications EP 1 041 947 and EP 1 423 062 referred toas the prior art coming closest ultimately attempt to optimize theinsole suggested in U.S. Pat. No. 5,404,659. In both cases, however, avery extensive dome-shaped structure is proposed which has thedisadvantages already mentioned above; in both cases, the golgi tendonorgan is to be stimulated by a dome-shaped structure whose target isdefined by the point of articulation of the lateral cuneiform, cuboidand navicular bones. This also applies to US 2002/0014024 A1 by the sameapplicant.

U.S. Pat. No. 2,423,622 A discloses a flat shoe insole having avirtually square-shaped elevation exactly and exclusively beneath thecuboid bone of the shoe wearer which is aligned laterally alongside thelongitudinal axis of the suggested shoe insole. To this extent, theknown shoe insole is the prior art coming closest to the presentinvention because it is designed entirely correctly insofar as the basicidea is concerned and was merely unable to take into account the currentinsights of the inventor which underlie the present invention orfundamentally new considerations spanning more than 60 years. Thedocument, which was certainly already very much ahead of its time,completely overcomes the misleading teachings of U.S. Pat. No. 2,287,341A according to which a shoe insole has elevations on the outer side inthe elongated position of the cuboid of the shoe wearer. The inventor isconvinced that shoe insoles designed in this way have poor healthbenefits.

U.S. Pat. No. 3,421,518 A likewise suggests an elevation on the outerside in the elongated position of the cuboid bone of the shoe wearer forthe insole of a shoe and therefore, with respect to medical engineering,does not go beyond the insights and disclosures of the above-cited U.S.Pat. No. 2,287,341 A.

The technical teaching of U.S. Pat. No. 2,154,997 A consists in theconstruction of a bottom foot lining in the elongated position of thecuboid bone of the shoe wearer which is now not only on the outer sidebut over the full width of the foot. This inhibits any inward rolling ofthe foot during the contact phase and is quite uncomfortable to wearbecause it is contrary to the natural gait. Further, a comparableteaching is disclosed in U.S. Pat. No. 2,421,088 A. In this respect, itremains to be noted that constructions such as these are diametricallyopposed to the present invention.

Finally, reference is made to U.S. Pat. No. 6,510,626 B1 which, withrespect to the insole for a shoe, likewise merely discloses outsideelevations in the elongated position of the cuboid bone of the shoewearer and to this extent does not go beyond the disclosures of U.S.Pat. No. 2,287,341 A and U.S. Pat. No. 3,421,518 A.

SUMMARY OF THE INVENTION

After intensive observations in everyday practice as a chiropractor, theinventor became convinced that all of the references evaluated aboveeither lead away from the solution to the underlying problem or at leastdo not solve it convincingly. This problem can be summarized by theobject of making available to the public an insole for a shoe whichenables natural walking without pain or fatigue.

According to one embodiment of the invention, the problem is solved byan insole for a shoe, wherein the insole has a flat back side indirection of the shoe outsole and a dome-shaped structure (12) on thefront side, and wherein

-   -   the dome-shaped structure (12) has a base surface of a maximum        of 25% of the insole surface,    -   the dome-shaped structure (12) is positioned under the cuboid        bone (4) of the shoe wearer,        wherein the insole according to the invention for a shoe is        characterized by the following features:    -   a longitudinal axis (16) can be associated with the dome-shaped        structure (12) at its apex, wherein the longitudinal axis (16)        of the dome-shaped structure (12) encloses an angle (φ) in a        range from 5° to 75° with the longitudinal axis of the insole.

A particularly preferred range for the angle (φ) between thelongitudinal axis (16) of the dome-shaped structure (12) and thelongitudinal axis of the insole is from 5° to 50°, particularlypreferably from 5° to 35°.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts walking motion;

FIG. 2 depicts contact points of a foot during the walking motion ofFIG. 1;

FIG. 3 is skelton a human foot;

FIG. 4 is skelton a human foot;

FIG. 5 is a truncated cone.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In a preferred embodiment form, the dome-shaped structure (12) (FIG. 5)of the insole according to the invention is positioned under the medialside of the cuboid bone (4) of the shoe wearer where the cuboid bone (4)borders the navicular bone (3) on one side and the calcaneus bone (2) onthe other side (FIG. 3). In this connection, reference is made on theone hand to FIG. 3 which shows the bone structure of a human foot andnames all of the important bones mentioned herein. On the other hand,reference is made to FIG. 4 which likewise shows the human foot in whichall of the bones essential to the invention are designated and, further,shows the goal of the dome-shaped structure corresponding to the presentinvention in one of the preferred embodiments thereof.

The dome-shaped structure (12) (FIG. 5) is constructed to be elastic. Itis produced from permanently elastic plastics and/or gel materials,constructional variations of various hardness being preferred. It wasshown in numerous trials upon which the present document is based thatin a preferred embodiment the base surface of the dome-shaped structure(12) of the insole according to the invention for a shoe can even have abase surface of only a maximum of 20%, or even a maximum of 15%, of theinsole surface. In particularly preferred embodiments, it is evenpossible to reduce the base surface of the dome-shaped structure (12) toa surface of 10% or less, particularly preferably even to a surface in arange from less than 4% to 8%, of the insole surface. In this case,however, the wearer of a shoe of this kind should train intensively torun on these insoles according to the invention with dome-shapedstructure (12) which have a particularly drastically reduced basesurface because otherwise it could be less comfortable under certaincircumstances.

The dome-shaped structure (12) is generally constructed in the form of atruncated cone or truncated pyramid which is rounded on the base sideand apex side. The height (15) of the dome-shaped structure (12) ispreferably in a range from 3 to 20 mm. The rounded apex (13) of thetruncated cone or truncated pyramid facing the cuboid bone (4) of theshoe wearer can accordingly be circular or square. In an embodimentform, which is particularly preferred and which is considered by theinventor to be the best, the truncated cone or truncated pyramid has arectangle or an ellipse at least at its rounded apex (13) facing thecuboid bone (4) of the shoe wearer, wherein the rectangle or ellipse hasa longitudinal-transverse ratio in a range of 1:1, or greater than 1:1,to 4:1 and particularly preferably in a range of 1.2:1 to 3:1.

When the truncated cone or truncated pyramid has a rectangle or ellipseat its rounded apex (13) facing the cuboid bone (4) of the shoe wearerwith a longitudinal-transverse ratio at least in a range of 1:1, orgreater than 1:1, to 4:1, it was shown to be particularly effective inthe trials upon which the present document is based when thelongitudinal axis (16) of the dome-shaped structure (12) extends alongthe medial edge of the cuboid bone (4) and particularly and preferablythen encloses an angle (φ) of 5° to 35°, particularly preferably anangle (φ) of 25° to 35°, with the longitudinal axis of the insole.

For an illustration of the dome-shaped structure (12) as truncated cone,reference is made particularly to FIG. 5 which shows a correspondingtruncated cone. The position of the angle (φ) is illustratedparticularly in FIG. 4.

In a first possible constructional variant of the insole according tothe invention, this insole is permanently connected to the dome-shapedstructure (12). This can be achieved in that the insole and dome-shapedstructure (12) are fabricated separately and subsequently indissolublyglued; this can also be achieved in that the insole and dome-shapedstructure (12) are cast integral from a suitable plastics materialwithout limiting in any way to these two possibilities.

In a second possible constructional variant of the insole according toone embodiment of the invention, the insole and dome-shaped structure(12) both have connection components, and the connection components ofthe insole are formed with the connection components of the dome-shapedstructure (12) in such a way that insole and dome-shaped structure (12)are connected to one another so as to be difficult to detach. Thisdetachability is desirable when the possibility of exchanging thedome-shaped structure (12) while retaining the insole is afforded as ispreferred by the inventor. When exchange of the dome-shaped structure(12) is possible, the latter can be replaced in a particularly simpleand convenient manner in case of wear or when a different hardnessand/or a different outer shape or dimension is desired.

In this case, the connection components between insole and dome-shapedstructure (12) are preferably selected from the list comprising:hook-and-loop strips; recessed grooves in the insole and springsengaging in the grooves under the base (14) of the dome-shaped structure(12); and recessed grooves in the base (14) of the dome-shaped structure(12) and springs engaging in the grooves at the front side of theinsole.

In case recessed grooves in the insole are selected as connectioncomponents between insole and dome-shaped structure (12), a preferredembodiment these recessed grooves in the insole extend at an angle of80° to 100° to the longitudinal axis (16) of the dome-shaped structure(12). Given this choice of angle at which the recessed grooves in theinsole and the springs engaging in the grooves in a corresponding mannerbelow the base (14) of the dome-shaped structure (12) extend virtuallyat right angles to the longitudinal axis (16) of the dome-shapedstructure (12), the insole and dome-shaped structure (12) are connectedto one another in a particularly resistant manner so that such analignment of grooves and springs is particularly suitable for athleticshoes. In a particularly preferred constructional variant of thedescribed embodiment form, the grooves which are recessed in the insoleextend up to at least an outer edge of the insole so that the springsbelow the base (14) of the dome-shaped structure (12) can be insertedinto the recessed grooves of the insole proceeding from the outer edgeof the insole.

In case recessed grooves in the base (14) of the dome-shaped structure(12) are selected as connection components between insole anddome-shaped structure (12), it is preferable when these recessed groovesextend along the longitudinal axis (16) of the dome-shaped structure(12). The springs corresponding to the recessed grooves along thelongitudinal axis (16) of the dome-shaped structure (12) are formed onthe front side of the insole. Insofar as the grooves are guided into thebase (14) of the dome-shaped structure (12) up to the outer edge of thedome-shaped structure (12), it is particularly simple and convenient toinsert the grooves proceeding from the end of the springs. Snap-inelements in the grooves and associated springs prevent an unintentionalslipping of the dome-shaped structure (12) relative to the insole on onehand and facilitate an exact alignment of the dome-shaped structure (12)relative to the insole on the other hand.

Insofar as the connection components between the insole and dome-shapedstructure (12) are realized by grooves and springs to be inserted intothe grooves, it is particularly preferable when the recessed grooves areundercut and the springs are formed so as to widen outward in acorresponding manner.

In another preferred embodiment, the construction of the dome-shapedstructure (12) and the connection thereof to the insole is realized by apreferably three-part component structure comprising base, center pieceand dome. In this case, the base which is generally made from aninelastic, durable plastic or from carbon fibers is positioned under theinsole ideally in the middle of a bottom structure of the insole whichcorresponds in an exactly fitting manner to the base and which receivesthe base, and the base comprises connection elements for connecting tothe center piece by frictional engagement. These connection elements forconnecting base and center piece by frictional engagement can beconstructed, for example, as matching eyelet/pin elements having asnap-in function.

Like the base, the center piece itself is preferably produced from aninelastic, durable plastic or from carbon fibers and is positioned abovethe base in the plane of the insole; to this end, the insole has acontinuous hole in the outer shape of the center piece. Ideally, thecenter piece can be inserted by guiding through the hole in the insolein an exactly fitting manner from above until it is pressed onto thebase for connecting to the latter.

On top, the center piece preferably has: either at least one recessedgroove, in which case the dome has the at least one matching springengaging in this groove, or at least one spring, in which case the domehas the at least one matching groove in which the spring of the centerpiece can engage.

The above-mentioned dome is constructed so as to be elastic and, forexample, is produced from permanently elastic plastic and/or from gelmaterial which may be covered with a suitable outer material ifrequired.

In a specific instance of the preferred embodiment form described above,the base and center piece can also be constructed as a cohesiveworkpiece which is either assembled before being inserted in an exactlyfitting manner through the hole in the insole, this time from below,from the two individually fabricated pieces, base and center piece, andpossibly glued, or is fabricated directly in one piece, in which casethis workpiece has a bottom part as base and a top part as center piece.

It is possible to form the insole as an integral component part of ashoe. In this case, the insole according to the invention is gluedand/or sewed to the outsole of a shoe and, as the case may be, also tothe outer material of this shoe.

In a particularly preferred embodiment form of the present invention, itis also possible that the insole is constructed as an insert for certainshoes. In this case, it is also possible for the insole to be producedand offered as a so-called 314 sole which can be fastened to a completeinsole inside a specific shoe by means of double-sided adhesive tapes.In so doing, it is common to shorten ¾ soles of this kind in the frontand, if necessary, on the sides until they fit into the given shoe.

Thus, while there have shown and described and pointed out fundamentalnovel features of the invention as applied to a preferred embodimentthereof, it will be understood that various omissions and substitutionsand changes in the form and details of the devices illustrated, and intheir operation, may be made by those skilled in the art withoutdeparting from the spirit of the invention. For example, it is expresslyintended that all combinations of those elements and/or method stepswhich perform substantially the same function in substantially the sameway to achieve the same results are within the scope of the invention.Moreover, it should be recognized that structures and/or elements and/ormethod steps shown and/or described in connection with any disclosedform or embodiment of the invention may be incorporated in any otherdisclosed or described or suggested form or embodiment as a generalmatter of design choice. It is the intention, therefore, to be limitedonly as indicated by the scope of the claims appended hereto.

1.-15. (canceled)
 16. An insole for a shoe, comprising: a back sideconfigured to face a shoe outsole; a front side opposite the back side;a dome-shaped structure arranged on the front side having a base surfacebeing a maximum of 25% of the insole surface positioned substantiallyunder a cuboid bone of a shoe wearer; and a longitudinal axis associatedwith the dome-shaped structure at an apex of the shaped structure,wherein the longitudinal axis of the dome-shaped structure encloses anangle having a range from about 5° to about 75° with a longitudinal axisof the insole.
 17. The insole according to claim 16, wherein thedome-shaped structure is positioned under a medial side of the cuboidbone of the shoe wearer where the cuboid bone borders a navicular boneon one side and a calcaneus bone on an other side.
 18. The insoleaccording to claim 16, wherein the base surface is a maximum of 15%, ofthe insole surface.
 19. The insole according to claim 16, wherein thebase surface is a maximum of 10%, of the insole surface.
 20. The insoleaccording to claim 16, wherein the dome-shaped structure has alongitudinal-transverse ratio in a range from about 1.2:1 to about 3:1.21. The insole according to claim 21, wherein the longitudinal axis ofthe dome-shaped structure extends along a medial edge of the cuboid boneand encloses an angle of 5° to 35° with the longitudinal axis of theinsole.
 22. The insole according to claim 16, wherein the dome-shapedstructure has a height in a range from about 3 mm to about 20 mm. 23.The insole according to claim 16, wherein the dome-shaped structure ispermanently connected to the insole.
 24. The insole according to claim16, wherein each of the insole and the dome-shaped structure have arespective connection components, wherein the connection component ofthe insole are formed with the connection components of the dome-shapedstructure for detachable connection of insole and dome-shaped structure.25. The insole according to claim 24, wherein the connection componentsare at least one of hook-and-loop strips, recessed grooves in the insoleand springs engaging in the grooves under the base of the dome-shapedstructure, and recessed grooves in the base of the dome-shaped structureand springs engaging in the grooves at the front side of the insole. 26.The insole according to claim 25, wherein the recessed grooves in theinsole extend at an angle of about 80° to about 100° to the longitudinalaxis of the dome-shaped structure.
 27. The insole according to claim 25,wherein the recessed grooves in the base of the dome-shaped structureextend along the longitudinal axis of the dome-shaped structure.
 28. Theinsole according to claim 25, wherein the respective recessed groovesare undercut and the respective springs are formed to widen outward. 29.The insole according to claim 16, wherein the insole is produced as aninsert for certain shoes.
 30. The insole according to claim 16, whereinthe insole is an integral component part of the shoe.